JP5139042B2 - Robot wrist device - Google Patents

Description

  According to the present invention, a flexible cable such as a signal line of an end effector, a power supply line, and a fluid transport pipe that guides a jet fluid or a working fluid that performs various processing on a workpiece in a narrow environment interferes with surrounding equipment. The present invention relates to a wrist device for a robot that can prevent the above.

  FIG. 6 is a partial cross-sectional view showing a wrist device 1 of a conventional robot. The wrist device 1 of the conventional robot is provided at the tip of the robot arm, and is driven by the first turning unit 2 that is driven to turn around a first axis L1 parallel to the axis of the tip. A swing part 3 that is angularly driven around a second axis L2 perpendicular to the first axis L1, and a second turn that is provided on the swing part 3 and that turns around a third axis L3 perpendicular to the second axis L2. Part 4.

First turning part 2, the holder 5 of the wrist device 1 has a pivot shaft 7 which is rotatably supported about the second axis L2 by a bearing 6. A first gear 8 is coaxially fixed to the swing shaft 7, a second gear 9 is meshed with the first gear 8, and rotational torque from the tip of the robot arm is transmitted to the second gear 9, The oscillating part 3 is configured to be able to oscillate around the second axis L <b> 2 with respect to the first slewing part 2 together with the second slewing part 4.

The holder 5 is also the first pivot shaft 12 which is rotatably supported by bearings 1 0 Thus about the fourth axis L4 are provided. A third gear 13 is coaxially fixed to one axial end portion of the first turning shaft 12, and a fourth gear 14 meshes with the third gear 13. Rotational torque from the tip of the robot arm is transmitted to the fourth gear 14. A fifth gear 15 is fixed to the other axial end of the first turning shaft 12. The sixth gear 16 meshes with the fifth gear 15. The fifth and sixth gears 15 and 16 are bevel gears.

  The sixth gear 16 is coaxially fixed to one end portion in the axial direction of the second turning shaft 20 that is rotatably supported around the third axis L3 by the bearings 18 and 19 on the holder 17 of the swinging portion 3. The second swivel unit 4 is fixed to the other axial end of the second swivel shaft 20, and an end effector 21 is detachably attached to the second swivel unit 4, so that any swing around the second axis L2 can be achieved. It is configured so that it can be turned to an arbitrary turning angle around the third axis L3 with a moving angle, and the end effector 21 can be placed in an optimum posture with respect to the workpiece to perform a predetermined work.

In such a conventional technique, the holder 5 of the first turning unit 2 has a base portion 25 disposed on the distal end side of the robot arm and a pair of arm portions 26a and 26b extending from the base portion 25, and has a substantially U shape. The swinging portion 3 is fitted between the arm portions 26a and 26b. The swing part 3 includes a holder 22 that is swingably connected around the second axis L <b> 2 by a pair of bearings 28 and 29, includes a first axis L <b> 1 that is substantially the center of the holder 22, and a second A partition wall 30 is formed near a virtual plane that is perpendicular to the axis L2 .
Further, in the vicinity of the partition wall 30, the fifth and sixth gears 15 and 16 are arranged close to each other and are configured to be overcrowded. Therefore, a signal line for transmitting / receiving a control signal for operating the end effector 21, a working fluid for driving an actuator provided in the end effector 21, and a fluid transport pipe for supplying a fluid such as cleaning or cooling liquid , And a cable in which power lines for supplying driving power to various actuators provided in the end effector 21 are bundled in a relaxed state from the end effector 21 to the distal end portion of the robot arm through the outside of the wrist device. There must be. Therefore, when work must be performed on a work in a narrow environment, there is a problem that the cable interferes with surrounding equipment and damages the cable. In order to avoid such cable damage, it is necessary to plan the robot operation in consideration of the space occupied by the cable stretched outside the wrist device 1 in a relaxed state. There is a problem that work cannot be performed on a workpiece.

  Another prior art wrist device that solves such a problem is described in Patent Document 1, for example. In this prior art, a cable that guides a wire to a welding torch mounted as an end effector on a rotating body that is a second turning portion is inserted into a through-hole formed in the rotating body, thereby bending and surrounding the cable. Prevents interference with equipment.

JP 2005-96073 A

  The prior art of Patent Document 1 has a problem that it cannot be attached to and detached from the tip of the robot arm.

  An object of the present invention is to provide a wrist device for a robot that can be attached to and detached from the tip of a robot arm.

The present invention is a wrist device for a robot that can be attached to and detached from the tip of a robot arm,
A substantially U-shaped and solid first swivel portion provided at the tip portion so as to be turnable about a first axis parallel to the axis of the tip portion, and having a pair of arms;
A hollow in which a first through hole is formed between each arm of the first swivel portion so as to be angularly displaceable about a second axis perpendicular to the first axis and extends along a third axis perpendicular to the second axis. Oscillating part of
A hollow having a second through hole formed at one end in the axial direction on the third axis of the swinging portion so as to be pivotable around a fourth axis parallel to the third axis and communicating with the first through hole. A second swivel part,
The swinging portion is formed with the first through hole so as to extend from the second turning portion to at least the second axis ,
It said first through hole, at the other axial end on the third axis of the oscillating member, and characterized that you have continuously expanded from the axial end portion toward the other axial end It is a wrist device of a robot that performs.

  According to the present invention, the first turning portion is provided at the tip of the robot arm. The first turning portion turns around a first axis parallel to the axis of the tip of the robot arm, has a pair of arms, and is formed in a substantially U shape. Each arm of the first turning portion is provided with a swinging portion having a first through hole so as to be angularly displaceable about the second axis. The first through hole extends along a third axis that is perpendicular to the second axis, and the swinging portion has a hollow structure by the first through hole. A second turning portion is provided at one end portion in the axial direction on the third axis of the swinging portion so as to be turnable around a fourth axis parallel to the third axis. The second turning portion has a second through hole, and the second through hole communicates with the first through hole of the swinging portion.

  Thus, since the first through hole is formed in the swinging portion and the second through hole is formed in the second turning portion, a cable is inserted into the first and second through holes, and the second through hole is formed. A signal line, working fluid, injecting fluid, power line or the like can be led to and connected to an end effector provided in the swivel unit. Therefore, unlike the prior art, there is no need to stretch the cable outside the wrist device, preventing the cable from interfering with surrounding equipment even in a narrow environment, and in a narrower space than in the past. It becomes possible to work smoothly.

  Further, according to the present invention, one arm of the first turning portion is provided with a swinging input gear to which a rotational force for angularly displacing the swinging portion around the second axis is transmitted from a tip portion of the robot arm. The other arm of the first turning part is provided with a turning input gear to which a rotational force for turning the second turning part around the fourth axis is transmitted from the tip of the robot arm.

  According to the present invention, since the swinging input gear is provided on one arm of the first turning shaft and the turning input gear is provided on the other arm, there is no need to greatly change the configuration of the wrist device. It is only necessary to change the configuration related to the rear-stage force transmission path compared to the swinging input gear and the swinging input gear, so that the conventional wrist device can be diverted, and the present invention is widely implemented at low cost. can do.

Furthermore, the present invention is characterized in that a cable protection tube extending over the first and second through holes is fixed to an inner peripheral portion facing the second through hole of the second turning portion.

  According to the present invention, since the cable protection tube fixed to the second turning part is provided in the first and second through holes, even if the cable is twisted by turning of the second turning part, the cable does not move. It is prevented that the inner peripheral surface facing the first through hole is slidably contacted and damaged.

  FIG. 1 is a partial enlarged sectional view showing a wrist device 40 of a robot according to an embodiment of the present invention. The wrist device 40 of the robot according to the present embodiment is provided at a distal end portion 42 of a robot arm 41 shown in FIG. 2 to be described later, and turns around a first axis L11 parallel to the axis L10 of the distal end portion 42, A substantially U-shaped first turning part 44 having arms 43a and 43b, and an arm 43a and 43b of the first turning part 44, which are angularly displaced around a second axis L12 perpendicular to the first axis L11. The swinging portion 46 formed with a first through hole 45 extending along the third axis L13 perpendicular to the second axis L12, and the axial end on the third axis L13 of the swinging portion 46 at the first axial end. A second swivel portion that swirls around a fourth axis L14 that is parallel to the three axis L13 and that has a second through hole 47 that communicates with the first through hole 45.

  One arm 43a of the first turning portion 44 is provided with a swinging input gear 51 to which a rotational force for angularly displacing the swinging portion 46 about the second axis L12 is transmitted from the distal end portion 42 of the robot arm 41. It is done. The other arm 43b of the first turning portion 44 is provided with a turning input gear 52 to which a rotational force for turning the second turning portion 48 around the fourth axis L14 is transmitted from the tip portion 42 of the robot arm 41. It is done.

  A swing transmission gear 53 meshes with the swing input gear 51. A rotational force is transmitted to the swing transmission gear 53 from the tip 42 of the robot arm 41 via a torque tube and a gear train (not shown). A turning transmission gear 54 meshes with the turning input gear 52. The turning transmission gear 54 receives a rotational force from the tip 42 of the robot arm 41 via a torque tube and a gear train (not shown). In this way, the swinging input gear 51 and the turning input gear 52 are individually input with the swinging rotational force and the turning rotational force output from the tip 42 of the robot arm 41 via the transmission gears 53 and 54, respectively. Is done.

  A base end portion 57 of the swinging portion 46 is interposed between the arms 43 a and 43 b of the first turning portion 44, and the first through hole 45 is formed in the base end portion 57.

The swing unit 46, generally-holder 55 having a cylindrical first holes 45 are provided, the rotational force of the pivot shaft 61 to the swing input gear 51 is fixed to the holder 55 is reached heat, oscillation section 46, the base end portion 57 side of the area each arm 43a, in a state of fitted between 43 b, it is swung by two bearings 63 and 64 about the second axis L12. A reduction gear may be interposed between the swing shaft 61 and the swing portion 46.

Further, when the turning input gear 52 is rotationally driven by the turning transmission gear 54, the rotational force is a turning shaft supported on the second axis L 12 by the bearing 59 on the holder 58 of the first turning portion 44. 66 and is input to the turning output member 71 through the bevel gear 67 fixed to the turning shaft 66 and the bevel gear 68 meshing therewith, and the turning output member 71 turns .

A straight cylindrical cable protection tube 93 extending over the first and second through holes 45 and 47 is fixed to the inner peripheral portion of the turning output member 71. The cable protection tube 93 may be fixed to the turning output member 71 by, for example, welding one end of the cable protection tube 93 in the axial direction to the turning output member 71.

  With such a cable protection tube 93, even if the second turning portion 48 turns, the cable protection tube 93 rotates in the same direction together with the second turning portion 48 and faces the first through hole 45 of the swinging portion 46. It is possible to prevent the cable 77 from slidably contacting the inner peripheral surface.

  2 is a perspective view showing a robot 91 including the wrist device 40 shown in FIG. 1, and FIG. 3 is a cross-sectional view of the vicinity of the wrist device 40 of the robot 91. As shown in FIG. The robot 91 includes a base 72 placed horizontally on a factory floor, a first arm 73 provided on the base 72 so as to be rotatable about a first axis J1 whose base end is vertical, and a first arm 73. The free end of the arm 73 has a second arm 74 provided with a lower end swingable around a horizontal second axis J2, and a third end J3 whose base end is horizontal at the upper end of the second arm 74. The third arm 75 is provided so as to be swingable, and the wrist device 40 is provided at the tip end portion 42 of the third arm 75 so as to be rotatable around the fourth axis J4. The first arm 73, the second arm 74, and the third arm 75 constitute the robot arm 41.

  In such a robot 91, the axis L10 of the tip 42 of the robot arm 41 described above forms the fourth axis J4, the first axis L11 exists on a common straight line with the fourth axis J4, and the second axis L12. Forms the fifth axis J5, and the third and fourth axes L13, L14 correspond to the sixth axis J6.

4 is a simplified plan view of the robot 91 shown in FIG. 2, FIG. 5 is a simplified side view of the wrist device 40, and FIG. 5 (1) is a state in which the swinging portion 46 is directed downward. FIG. 5B shows a state where the swinging portion 46 is directed upward. Cable 77, such as signal lines and power supply lines are led from the third arm 75 through the outer of the base 7 2, the first arm 73 and second arm 74 to the outside through the grommet 78, again the second grommet 79 is guided into the first turning portion 44 of the wrist device 40 through 79, inserted through the first through hole 45 of the swinging portion 46 from the space 80 between the arms 43a and 43b, and further the second turning portion 48 of the second turning portion 48. The second through hole 47 is inserted into the end effector connected to the second turning portion 48, for example, the hand 81, and is guided through the third grommet 82.

  In this way, the cable 77 can be inserted into the first turning portion 44 of the wrist device 40 and inserted through the first and second through holes 45 and 47 and connected to the hand 81. As shown, even if the hand 81 is directed around the fifth axis J5 to one side, for example, downward, the cable 77 is smoothly curved with a curvature as large as possible in the first and second through holes 45 and 47. Following this, even if the hand 81 is angularly displaced in the reverse direction with respect to the fifth axis J5 as shown in FIG. 5 (2), the cable 77 is large in the first and second through holes 45 and 47 due to its elastic recovery force. It bends with curvature and can follow the hand 81.

  Thus, even if the hand 81 is swung around the fifth axis J5, the cable 77 does not protrude outward from the first swivel portion 44, the swivel portion 46, and the second swivel portion 48, and the first and second penetrations. Since it can be curved and follow in the holes 45 and 47 with a large curvature, the cable 77 can be prevented from being damaged, and even in a confined environment, the cable 77 does not interfere with other equipment, and the predetermined value can be obtained by the hand 81. Work, for example, the semiconductor wafer can be taken out from the holder or the hoop, or can be smoothly carried into and out of the processing chamber.

  In addition, since the wrist device 40 is provided with the swinging input gear 51 and the turning input gear 52, it is not necessary to greatly change the configuration of the wrist device 40, for example, the swinging input gear 51 and the turning input gear. It is only necessary to newly change the stage after 52, that is, only the swinging part 46 and the second turning part 48, and this makes it possible to divert the existing wrist device and implement the present invention at low cost.

Further, the user can exchange the hollow wrist device 40 according to the present invention and the conventional solid wrist device with respect to the distal end portion 42 of the robot arm 41 for one robot according to the application. For example, when a wide range of movement of the wrist device is required, when entering a narrow environment, when attaching a tool that does not require signal and power supply to the second swivel unit 48 as an end effector, A conventional solid wrist device can be used by being attached to the distal end portion 42 of the robot arm 41, and the tool 77 attached as an end effector needs to be stored without protruding outside the wrist. In this case, the wrist device 40 according to the present invention can be used by being attached to the distal end portion 42 of the robot arm 41 in place of the conventional solid wrist device.

It is a partial expanded sectional view which shows the wrist apparatus 40 of the robot of one Embodiment of this invention. It is a perspective view of the robot 91 with which the wrist device 40 of the robot shown in FIG. 1 was mounted | worn. 3 is a cross-sectional view of the wrist device 40 with a part cut away. FIG. 3 is a simplified plan view of a robot 91. FIG. FIG. 5A is a simplified side view for explaining the operation of the wrist device 40. FIG. 5A shows a state in which the swinging portion 46 and the second turning portion 48 are directed downward, and FIG. The state which turned the moving part 46 and the 2nd turning part 48 upward is shown. 1 is a partial cross-sectional view showing a wrist device 1 of a conventional robot.

Explanation of symbols

40 Robot wrist device 41 Robot arm 42 Tip 43a, 43b Arm 44 First turning part 45 First through hole 46 Swing part 47 Second through hole 48 Second turning part 51 Swing input gear 52 Swing input gear 53 Transmission gear for swing 54 Transmission gear for rotation 73 First arm 74 Second arm 75 Third arm 77 Cable 81 Hand 91 Robot 92 Base

Claims (3)

A robot wrist device that can be attached to and detached from the tip of a robot arm,
A substantially U-shaped and solid first swivel portion provided at the tip portion so as to be turnable about a first axis parallel to the axis of the tip portion, and having a pair of arms;
A hollow in which a first through hole is formed between each arm of the first swivel portion so as to be angularly displaceable about a second axis perpendicular to the first axis and extends along a third axis perpendicular to the second axis. Oscillating part of
A hollow having a second through hole formed at one end in the axial direction on the third axis of the swinging portion so as to be pivotable around a fourth axis parallel to the third axis and communicating with the first through hole. A second swivel part,
The swinging portion is formed with the first through hole so as to extend from the second turning portion to at least the second axis ,
It said first through hole, at the other axial end on the third axis of the oscillating member, and characterized that you have continuously expanded from the axial end portion toward the other axial end Robot wrist device.   One arm of the first turning part is provided with a swinging input gear to which a rotational force for angularly displacing the swinging part around the second axis is transmitted from the tip of the robot arm, and the first turning part 2. The robot according to claim 1, wherein the other arm of the robot is provided with a turning input gear to which a rotational force for turning the second turning portion around the fourth axis is transmitted from the tip portion of the robot arm. Wrist device.   3. The robot wrist device according to claim 1, wherein a cable protection tube extending over the first and second through holes is fixed to an inner peripheral portion facing the second through hole of the second turning portion. .

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